Preheat the grill to medium-high heat.

In a large bowl, combine the sliced zucchini, red bell pepper, yellow bell pepper, mushrooms, and red onion.

Drizzle with olive oil, oregano, garlic powder, salt, and pepper. Toss to coat evenly.

Place the vegetables on the grill and cook for about 5-7 minutes, turning occasionally, until tender and slightly charred.

Remove from the grill and set aside.

Heat a skillet over medium heat.

Place one tortilla in the skillet, sprinkle half with mozzarella cheese, add a portion of grilled vegetables, and top with feta cheese.

Fold the tortilla in half and cook for about 3-4 minutes on each side until golden brown and the cheese is melted.

Repeat with remaining tortillas and filling.

Cut the quesadillas into wedges and serve warm with your choice of salsa or sour cream.